Oh boy, here we go......
Seriously though, I recommend a van based on your need to haul six people.
If they're still small kids, you can
get away with a crew cab. If the trailer is fairly light, you can
get away with a larger gas engine.
But if you need room to haul adults (or kids that like to "pick" at each other) and the trailer is heavier, I would recommend a 1 ton diesel van.
First trip you take and don't have people sitting on top of each other fro a couple hours, or have enough enough room to seperate teh kids a bit and still haul all the gear that six people are going to require you'll be glad you have the space, capacity and CGVWR that one ton diesel van is going to give you.
If it's you're only
vehicle, well, that big of a van can be somewhat cumbersome in day to day use.
Problem is, if it's going to be your only vehicle your needs don't really line up with each other.
Something is going to suffer somewhere. you just have to choose what
you're willing to sacrifice....